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@@ -0,0 +1,112 @@
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+const mediaFileToWavFile = async (mediaObj, options = {}) => {
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+ let _file = null
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+ // if (mediaObj.url) {
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+ // let res = await getFile(mediaObj.url)
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+ // if (res.data === 1) {
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+ // console.log('获取媒体文件失败')
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+ // return ''
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+ // }
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+ // _file = new File([res.data], mediaObj.name, { type: mediaObj.type })
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+ // } else {
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+ _file = mediaObj
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+ // }
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+
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+ // 添加参数配置
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+ const { sampleRate = 22050, optimize = false } = options
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+
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+ return new Promise((resolve) => {
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+ try {
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+ const reader = new FileReader();
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+ reader.onload = async (e) => {
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+ const audioContext = new (window.AudioContext || window.webkitAudioContext)();
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+ const buffer = await audioContext.decodeAudioData(e.target.result);
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+
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+ let targetBuffer = buffer;
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+
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+ // 如果启用优化或指定采样率
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+ if (optimize || sampleRate !== buffer.sampleRate) {
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+ const targetSampleRate = Math.min(sampleRate, buffer.sampleRate);
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+
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+ const offlineAudioContext = new OfflineAudioContext({
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+ numberOfChannels: buffer.numberOfChannels,
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+ length: Math.floor(buffer.length * targetSampleRate / buffer.sampleRate),
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+ sampleRate: targetSampleRate
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+ });
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+
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+ const source = offlineAudioContext.createBufferSource();
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+ source.buffer = buffer;
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+ source.connect(offlineAudioContext.destination);
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+ source.start();
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+
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+ targetBuffer = await offlineAudioContext.startRendering();
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+ }
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+
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+ const wavBlob = bufferToWav(targetBuffer);
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+ const fileName = mediaObj.name ?
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+ mediaObj.name.replace(/\.[^/.]+$/, "") + '.wav' :
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+ 'audio.wav';
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+ const audioFile = new File([wavBlob], fileName, { type: 'audio/wav' });
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+
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+ console.log(`转换成功，采样率: ${targetBuffer.sampleRate}Hz，文件大小: ${(audioFile.size / 1024 / 1024).toFixed(2)}MB`)
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+ resolve(audioFile)
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+ }
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+ reader.readAsArrayBuffer(_file);
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+ } catch (error) {
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+ console.log('音频提取失败', error)
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+ resolve('')
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+ }
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+ })
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+}
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+
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+function bufferToWav(buffer) {
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+ const numChannels = buffer.numberOfChannels;
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+ const sampleRate = buffer.sampleRate;
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+ const format = 1; // PCM
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+ const bitDepth = 16;
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+
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+ const bytesPerSample = bitDepth / 8;
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+ const blockAlign = numChannels * bytesPerSample;
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+ const byteRate = sampleRate * blockAlign;
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+ const dataSize = buffer.length * blockAlign;
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+
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+ const bufferLength = 44 + dataSize;
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+ const arrayBuffer = new ArrayBuffer(bufferLength);
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+ const view = new DataView(arrayBuffer);
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+
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+ // WAV 头部
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+ writeString(view, 0, 'RIFF');
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+ view.setUint32(4, bufferLength - 8, true);
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+ writeString(view, 8, 'WAVE');
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+ writeString(view, 12, 'fmt ');
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+ view.setUint32(16, 16, true); // fmt chunk size
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+ view.setUint16(20, format, true);
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+ view.setUint16(22, numChannels, true);
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+ view.setUint32(24, sampleRate, true);
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+ view.setUint32(28, byteRate, true);
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+ view.setUint16(32, blockAlign, true);
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+ view.setUint16(34, bitDepth, true);
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+ writeString(view, 36, 'data');
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+ view.setUint32(40, dataSize, true);
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+
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+ // 写入 PCM 数据
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+ let offset = 44;
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+ for (let i = 0; i < buffer.length; i++) {
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+ for (let channel = 0; channel < numChannels; channel++) {
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+ const sample = Math.max(-1, Math.min(1, buffer.getChannelData(channel)[i]));
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+ view.setInt16(offset, sample < 0 ? sample * 0x8000 : sample * 0x7FFF, true);
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+ offset += 2;
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+ }
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+ }
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+
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+ return new Blob([arrayBuffer], { type: 'audio/wav' });
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+}
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+
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+function writeString(view, offset, string) {
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+ for (let i = 0; i < string.length; i++) {
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+ view.setUint8(offset + i, string.charCodeAt(i));
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+ }
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+}
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+
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+export {
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+ mediaFileToWavFile
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+}
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qgt